/* * syntax_highlight.hpp * C and Lua syntax highlighting for the MontaukOS text editor * Activated for .c, .h, and .lua files * Copyright (c) 2026 Daniel Hammer */ #pragma once #include using namespace gui; enum SynLanguage : uint8_t { SYN_LANG_NONE, SYN_LANG_C, SYN_LANG_LUA, }; // ============================================================================ // Token types // ============================================================================ enum SynToken : uint8_t { SYN_NORMAL, SYN_KEYWORD, SYN_TYPE, SYN_PREPROCESSOR, SYN_STRING, SYN_CHAR, SYN_COMMENT, SYN_NUMBER, SYN_OPERATOR, }; struct SynState { bool in_block_comment; SynToken long_token; int long_bracket_eqs; }; // ============================================================================ // Colors for each token type // ============================================================================ inline Color syn_color(SynToken tok) { switch (tok) { case SYN_KEYWORD: return Color::from_rgb(0xC5, 0x62, 0x8C); // magenta-pink case SYN_TYPE: return Color::from_rgb(0x2E, 0x86, 0xAB); // teal case SYN_PREPROCESSOR: return Color::from_rgb(0x8B, 0x6E, 0xB5); // purple case SYN_STRING: return Color::from_rgb(0x6A, 0x9F, 0x3A); // green case SYN_CHAR: return Color::from_rgb(0x6A, 0x9F, 0x3A); // green case SYN_COMMENT: return Color::from_rgb(0x7A, 0x7A, 0x7A); // gray case SYN_NUMBER: return Color::from_rgb(0xC9, 0x7E, 0x2A); // orange case SYN_OPERATOR: return Color::from_rgb(0x40, 0x40, 0x40); // dark gray default: return Color::from_rgb(0x1E, 0x1E, 0x1E); // near-black } } // ============================================================================ // Keyword / type lookup // ============================================================================ inline bool syn_is_alpha(char c) { return (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') || c == '_'; } inline bool syn_is_alnum(char c) { return syn_is_alpha(c) || (c >= '0' && c <= '9'); } inline bool syn_is_digit(char c) { return c >= '0' && c <= '9'; } inline bool syn_is_hex(char c) { return syn_is_digit(c) || (c >= 'a' && c <= 'f') || (c >= 'A' && c <= 'F'); } inline void syn_set_token(SynToken* out, int out_len, int idx, SynToken tok) { if (out && idx >= 0 && idx < out_len) out[idx] = tok; } inline void syn_fill_tokens(SynToken* out, int out_len, int start, int end, SynToken tok) { if (!out) return; if (start < 0) start = 0; if (end > out_len) end = out_len; for (int i = start; i < end; i++) out[i] = tok; } inline bool syn_streq(const char* buf, int len, const char* kw) { int i = 0; while (i < len && kw[i]) { if (buf[i] != kw[i]) return false; i++; } return i == len && kw[i] == '\0'; } inline SynToken syn_classify_c_word(const char* buf, int len) { // C keywords static const char* keywords[] = { "auto", "break", "case", "const", "continue", "default", "do", "else", "enum", "extern", "for", "goto", "if", "inline", "register", "restrict", "return", "sizeof", "static", "struct", "switch", "typedef", "union", "volatile", "while", "NULL", "true", "false", "nullptr", }; // C types static const char* types[] = { "void", "char", "short", "int", "long", "float", "double", "signed", "unsigned", "bool", "_Bool", "int8_t", "int16_t", "int32_t", "int64_t", "uint8_t", "uint16_t", "uint32_t", "uint64_t", "size_t", "ssize_t", "ptrdiff_t", "intptr_t", "uintptr_t", "FILE", }; for (int i = 0; i < (int)(sizeof(keywords) / sizeof(keywords[0])); i++) { if (syn_streq(buf, len, keywords[i])) return SYN_KEYWORD; } for (int i = 0; i < (int)(sizeof(types) / sizeof(types[0])); i++) { if (syn_streq(buf, len, types[i])) return SYN_TYPE; } return SYN_NORMAL; } inline SynToken syn_classify_lua_word(const char* buf, int len) { static const char* keywords[] = { "and", "break", "do", "else", "elseif", "end", "false", "for", "function", "goto", "if", "in", "local", "nil", "not", "or", "repeat", "return", "then", "true", "until", "while", }; static const char* builtins[] = { "_ENV", "_G", "_VERSION", "assert", "collectgarbage", "coroutine", "debug", "dofile", "error", "getmetatable", "io", "ipairs", "load", "loadfile", "math", "next", "os", "package", "pairs", "pcall", "print", "rawequal", "rawget", "rawlen", "rawset", "require", "select", "setmetatable", "string", "table", "tonumber", "tostring", "type", "utf8", "warn", "xpcall", }; for (int i = 0; i < (int)(sizeof(keywords) / sizeof(keywords[0])); i++) { if (syn_streq(buf, len, keywords[i])) return SYN_KEYWORD; } for (int i = 0; i < (int)(sizeof(builtins) / sizeof(builtins[0])); i++) { if (syn_streq(buf, len, builtins[i])) return SYN_TYPE; } return SYN_NORMAL; } inline SynToken syn_classify_word(SynLanguage lang, const char* buf, int len) { switch (lang) { case SYN_LANG_C: return syn_classify_c_word(buf, len); case SYN_LANG_LUA: return syn_classify_lua_word(buf, len); default: return SYN_NORMAL; } } inline SynState syn_make_state() { SynState state = {}; state.in_block_comment = false; state.long_token = SYN_NORMAL; state.long_bracket_eqs = -1; return state; } inline bool syn_match_lua_long_bracket_open(const char* line, int len, int i, int& eqs, int& span) { if (i >= len || line[i] != '[') return false; int j = i + 1; while (j < len && line[j] == '=') j++; if (j < len && line[j] == '[') { eqs = j - i - 1; span = j - i + 1; return true; } return false; } inline bool syn_match_lua_long_bracket_close(const char* line, int len, int i, int eqs, int& span) { if (i >= len || line[i] != ']') return false; int j = i + 1; for (int k = 0; k < eqs; k++) { if (j >= len || line[j] != '=') return false; j++; } if (j < len && line[j] == ']') { span = j - i + 1; return true; } return false; } inline void syn_consume_number(const char* line, int len, int& i, SynToken* out, int out_len, bool c_style_suffixes) { int start = i; if (line[i] == '0' && i + 1 < len && (line[i + 1] == 'x' || line[i + 1] == 'X')) { i += 2; while (i < len && syn_is_hex(line[i])) i++; if (i < len && line[i] == '.' && !(i + 1 < len && line[i + 1] == '.')) { i++; while (i < len && syn_is_hex(line[i])) i++; } if (i < len && (line[i] == 'p' || line[i] == 'P')) { int exp = i + 1; if (exp < len && (line[exp] == '+' || line[exp] == '-')) exp++; if (exp < len && syn_is_digit(line[exp])) { i = exp + 1; while (i < len && syn_is_digit(line[i])) i++; } } } else { if (line[i] == '.') i++; while (i < len && syn_is_digit(line[i])) i++; if (i < len && line[i] == '.' && !(i + 1 < len && line[i + 1] == '.')) { i++; while (i < len && syn_is_digit(line[i])) i++; } if (i < len && (line[i] == 'e' || line[i] == 'E')) { int exp = i + 1; if (exp < len && (line[exp] == '+' || line[exp] == '-')) exp++; if (exp < len && syn_is_digit(line[exp])) { i = exp + 1; while (i < len && syn_is_digit(line[i])) i++; } } } if (c_style_suffixes) { while (i < len && (line[i] == 'u' || line[i] == 'U' || line[i] == 'l' || line[i] == 'L' || line[i] == 'f' || line[i] == 'F')) i++; } syn_fill_tokens(out, out_len, start, i, SYN_NUMBER); } // ============================================================================ // Per-line highlighter // ============================================================================ // // Fills `out[]` with SynToken values for each character in the line. // `state` carries the multi-line syntax state across lines: // - pass in the state from the previous line // - on return, updated for the next line // // `line` points to the first char of the line, `len` is its length // (excluding the newline). `out` can be null if only state tracking is needed. inline void syn_highlight_line_c(const char* line, int len, SynToken* out, int out_len, SynState& state) { int i = 0; while (i < len) { // ---- Block comment continuation ---- if (state.in_block_comment) { while (i < len) { if (i + 1 < len && line[i] == '*' && line[i + 1] == '/') { syn_set_token(out, out_len, i, SYN_COMMENT); syn_set_token(out, out_len, i + 1, SYN_COMMENT); i += 2; state.in_block_comment = false; break; } syn_set_token(out, out_len, i, SYN_COMMENT); i++; } continue; } char c = line[i]; // ---- Line comment ---- if (c == '/' && i + 1 < len && line[i + 1] == '/') { syn_fill_tokens(out, out_len, i, len, SYN_COMMENT); break; } // ---- Block comment start ---- if (c == '/' && i + 1 < len && line[i + 1] == '*') { state.in_block_comment = true; syn_set_token(out, out_len, i, SYN_COMMENT); syn_set_token(out, out_len, i + 1, SYN_COMMENT); i += 2; continue; } // ---- Preprocessor directive ---- if (c == '#') { // Check that only whitespace precedes the # bool is_pp = true; for (int j = 0; j < i; j++) { if (line[j] != ' ' && line[j] != '\t') { is_pp = false; break; } } if (is_pp) { while (i < len) { // Handle line-comment inside preprocessor if (i + 1 < len && line[i] == '/' && line[i + 1] == '/') { syn_fill_tokens(out, out_len, i, len, SYN_COMMENT); break; } // Handle block comment start inside preprocessor if (i + 1 < len && line[i] == '/' && line[i + 1] == '*') { state.in_block_comment = true; syn_set_token(out, out_len, i, SYN_COMMENT); syn_set_token(out, out_len, i + 1, SYN_COMMENT); i += 2; // Continue consuming as comment while (i < len) { if (i + 1 < len && line[i] == '*' && line[i + 1] == '/') { syn_set_token(out, out_len, i, SYN_COMMENT); syn_set_token(out, out_len, i + 1, SYN_COMMENT); i += 2; state.in_block_comment = false; break; } syn_set_token(out, out_len, i, SYN_COMMENT); i++; } continue; } syn_set_token(out, out_len, i, SYN_PREPROCESSOR); i++; } continue; } } // ---- String literal ---- if (c == '"') { syn_set_token(out, out_len, i, SYN_STRING); i++; while (i < len) { if (line[i] == '\\' && i + 1 < len) { syn_set_token(out, out_len, i, SYN_STRING); syn_set_token(out, out_len, i + 1, SYN_STRING); i += 2; continue; } if (line[i] == '"') { syn_set_token(out, out_len, i, SYN_STRING); i++; break; } syn_set_token(out, out_len, i, SYN_STRING); i++; } continue; } // ---- Character literal ---- if (c == '\'') { syn_set_token(out, out_len, i, SYN_CHAR); i++; while (i < len) { if (line[i] == '\\' && i + 1 < len) { syn_set_token(out, out_len, i, SYN_CHAR); syn_set_token(out, out_len, i + 1, SYN_CHAR); i += 2; continue; } if (line[i] == '\'') { syn_set_token(out, out_len, i, SYN_CHAR); i++; break; } syn_set_token(out, out_len, i, SYN_CHAR); i++; } continue; } // ---- Numbers ---- if (syn_is_digit(c) || (c == '.' && i + 1 < len && syn_is_digit(line[i + 1]))) { syn_consume_number(line, len, i, out, out_len, true); continue; } // ---- Identifiers / keywords / types ---- if (syn_is_alpha(c)) { int start = i; while (i < len && syn_is_alnum(line[i])) i++; SynToken tok = syn_classify_word(SYN_LANG_C, line + start, i - start); syn_fill_tokens(out, out_len, start, i, tok); continue; } // ---- Operators ---- if (c == '+' || c == '-' || c == '*' || c == '/' || c == '%' || c == '=' || c == '!' || c == '<' || c == '>' || c == '&' || c == '|' || c == '^' || c == '~' || c == '?' || c == ':') { syn_set_token(out, out_len, i, SYN_OPERATOR); i++; continue; } // ---- Everything else (whitespace, braces, parens, etc.) ---- syn_set_token(out, out_len, i, SYN_NORMAL); i++; } } inline void syn_highlight_line_lua(const char* line, int len, SynToken* out, int out_len, SynState& state) { int i = 0; while (i < len) { if (state.long_token != SYN_NORMAL) { int span = 0; if (syn_match_lua_long_bracket_close(line, len, i, state.long_bracket_eqs, span)) { syn_fill_tokens(out, out_len, i, i + span, state.long_token); i += span; state.long_token = SYN_NORMAL; state.long_bracket_eqs = -1; continue; } syn_set_token(out, out_len, i, state.long_token); i++; continue; } char c = line[i]; if (c == '-' && i + 1 < len && line[i + 1] == '-') { int eqs = 0; int span = 0; if (i + 2 < len && syn_match_lua_long_bracket_open(line, len, i + 2, eqs, span)) { syn_fill_tokens(out, out_len, i, i + 2 + span, SYN_COMMENT); i += 2 + span; state.long_token = SYN_COMMENT; state.long_bracket_eqs = eqs; continue; } syn_fill_tokens(out, out_len, i, len, SYN_COMMENT); break; } if (c == '"' || c == '\'') { char quote = c; syn_set_token(out, out_len, i, SYN_STRING); i++; while (i < len) { if (line[i] == '\\' && i + 1 < len) { syn_set_token(out, out_len, i, SYN_STRING); syn_set_token(out, out_len, i + 1, SYN_STRING); i += 2; continue; } syn_set_token(out, out_len, i, SYN_STRING); if (line[i] == quote) { i++; break; } i++; } continue; } int eqs = 0; int span = 0; if (syn_match_lua_long_bracket_open(line, len, i, eqs, span)) { syn_fill_tokens(out, out_len, i, i + span, SYN_STRING); i += span; state.long_token = SYN_STRING; state.long_bracket_eqs = eqs; continue; } if (syn_is_digit(c) || (c == '.' && i + 1 < len && syn_is_digit(line[i + 1]))) { syn_consume_number(line, len, i, out, out_len, false); continue; } if (syn_is_alpha(c)) { int start = i; while (i < len && syn_is_alnum(line[i])) i++; SynToken tok = syn_classify_word(SYN_LANG_LUA, line + start, i - start); syn_fill_tokens(out, out_len, start, i, tok); continue; } if (c == '+' || c == '-' || c == '*' || c == '/' || c == '%' || c == '^' || c == '#' || c == '=' || c == '<' || c == '>' || c == '~' || c == ':' || c == '.' || c == ',' || c == ';' || c == '(' || c == ')' || c == '{' || c == '}' || c == '[' || c == ']') { syn_set_token(out, out_len, i, SYN_OPERATOR); i++; continue; } syn_set_token(out, out_len, i, SYN_NORMAL); i++; } } inline void syn_highlight_line(const char* line, int len, SynToken* out, int out_len, SynLanguage lang, SynState& state) { if (!line || len <= 0) return; switch (lang) { case SYN_LANG_C: syn_highlight_line_c(line, len, out, out_len, state); break; case SYN_LANG_LUA: syn_highlight_line_lua(line, len, out, out_len, state); break; default: syn_fill_tokens(out, out_len, 0, len, SYN_NORMAL); break; } } // ============================================================================ // Extension check // ============================================================================ inline bool syn_path_ends_with(const char* path, const char* suffix) { if (!path || !suffix) return false; int path_len = 0; while (path[path_len]) path_len++; int suffix_len = 0; while (suffix[suffix_len]) suffix_len++; if (path_len < suffix_len) return false; for (int i = 0; i < suffix_len; i++) { if (path[path_len - suffix_len + i] != suffix[i]) return false; } return true; } inline SynLanguage syn_detect_language(const char* filepath) { if (!filepath || filepath[0] == '\0') return SYN_LANG_NONE; if (syn_path_ends_with(filepath, ".c") || syn_path_ends_with(filepath, ".h")) return SYN_LANG_C; if (syn_path_ends_with(filepath, ".lua")) return SYN_LANG_LUA; return SYN_LANG_NONE; }